1. Field
The presently disclosed subject matter relates to a vehicular lighting fixture, and more particularly to a vehicular lighting fixture capable of preventing a dark zone from being formed in a synthesized light distribution pattern.
2. Description of the Related Art
Conventionally, a vehicular lighting fixture which forms a synthesized light distribution pattern by a plurality of light distribution patterns is known (see, for example, Japanese Patent No. 4080780).
FIG. 6 illustrates an example of a vehicular lighting fixture which forms a synthesized light distribution pattern by a plurality of light distribution patterns. FIG. 7 is a perspective view of a shade used in the vehicular lighting fixture illustrated in FIG. 6.
As illustrated in FIG. 6, a conventional vehicular lighting fixture 200, which forms a synthesized light distribution pattern by a plurality of light distribution patterns, includes a projection lens 210, an LED (light-emitting diode) light source 220, a first reflection surface 230 arranged in the irradiation direction of the LED light source 220, and a shade 240 arranged between the projection lens 210 and the LED light source 220. As illustrated in FIG. 7, the upper surface 241 of the shade 240 includes: an upper stage reflection surface 241a corresponding to a shape formed by horizontally extending a first curved end edge e1a from the side of the projection lens 210 to the side of the LED light source 220 (in −Z direction); an inclined reflection surface 241b corresponding to a shape formed in such a manner that an inclined end edge e1b, which extends continuously and obliquely downward from the first curved end edge e1a, is horizontally extended from the side of the projection lens 210 to the side of the LED light source 220; and a lower stage reflection surface 241c corresponding to a shape formed in such a manner that a second curved end edge e1c connected to the inclined end edge e1b is horizontally extended from the side of the projection lens 210 to the side of the LED light source 220.
As illustrated in FIG. 6, in the vehicular lighting fixture 200 configured as described above, an irradiation light Ray1 from the LED light source 220 reaches the first reflection surface 230, and is then reflected by the first reflection surface 230, so as to be condensed in the vicinity of the inclined end edge e1b of the upper surface 241 of the shade 240. The light Ray 1 then passes through the projection lens 210, so as to form a basic light distribution pattern P0 (see FIG. 9) which has cutoff lines CLa to CLc defined by the projection lens side end edges (the first curved end edge e1a, the inclined end edge e1b, the second curved end edge e1b) and which is wide in the vertical and horizontal directions.
Further, a reflected light beam Ray2 from the first reflection surface 230 reaches the upper stage reflection surface 241a, and is then reflected by the upper stage reflection surface 241a, and passes through the projection lens 210, so as to form a first additional light distribution pattern P1 (see FIG. 9). The pattern P1 has the cutoff line CLa defined by the first curved end edge e1a and which is superimposed on the basic light distribution pattern P0.
Further, the reflected beam Ray2 from the first reflection surface 230 reached the inclined reflection surface 241b, and is then reflected by the inclined reflection surface 241b, and passes through the projection lens 210, so as to form a second additional light distribution pattern P2 (see FIG. 9). The second distribution pattern has the cutoff line CLb defined by the inclined end edge e1b and which is superimposed on the basic light distribution pattern P0.
Further, the reflected light Ray2 from the first reflection surface 230 reaches the lower stage reflection surface 241c, and is then reflected by the lower stage reflection surface 241c, and passes through the projection lens 210, so as to form a third additional light distribution pattern P3 (see FIG. 9). The third additional light distribution pattern P3 has the cutoff line CLc defined by the second curved end edge e1c and which is superimposed on the basic light distribution pattern P0.
As described above, a synthesized light distribution pattern P is formed by the plurality of light distribution patterns P0 to P3 which are respectively formed by the reflection surface 230, and the reflection surfaces 241a to 241c. 